The situation in Ukraine's east can be resolved by amending the Constitution in regard to enhancing powers of local authorities and the status of the Russian language, leader of the Batkivschyna Party, Ukrainian presidential candidate Yulia Tymoshenko said.

No one can tell Ukraine which constitution and laws to pass and which foreign course to choose, Tymoshenko said at a news conference in Donetsk on Friday.

"I think that Russia has overreached its powers significantly by imposing ultimatums on Ukraine regarding our domestic policy," she said.

It is necessary to search for a compromise between Ukrainian citizens residing in east and west and the referendum, which residents of south-east demand, should not be held, Tymoshenko said.

"We have had such a referendum already… This referendum can not be recognized and can not be considered legitimate, thus we think that Crimea's territory is occupied," she said.

The presidential elections of May 25 could be a stabilizing factor and they should not be postponed, Tymoshenko said.